SAP Migration to AWS Cloud Guide

SAP Migration to AWS Cloud Guide. The scope of this document is to give an overview of how to migrate an SAP ECC system running on an on-premise data center to Amazon Web Services (AWS) cloud using the SAP migration tool DMO (Database Migration Option). The source database is running on a non-HANA or AnyDB (DB2, Oracle, MySQL) database, which will be migrated to SAP HANA on AWS cloud along with the SAP ECC migration.

Brief background of SAP and AWS alliance and support prerequisites

AWS is an SAP Global Technology Partner. Running SAP on AWS has the following benefits:

Lower TCO

Replacement of CapEx with OpEx by removing any upfront cost

Agility and speed

Flexibility

SAP Migration to AWS Cloud: Support Prerequisites

SAP on AWS is only supportable if a fee-based AWS support agreement is in place

SAP production systems running on AWS must operate within the Amazon Virtual Public Cloud (VPC). End-user access to the application should be routed through the customer intranet and the Amazon VPC tunnel to the applications hosted in AWS.

It is recommended to only use EBS (Amazon Elastic Block Store) optimized EC2 instances for SAP production databases.

AWS and SAP HANA Migration Options

There are various tools and methodologies available for SAP migration to AWS cloud.

SAP HANA classical migration with SWPM

SAP offers the SAP HANA classical migration option for migrating from other AnyDB to SAP HANA. This option uses the SAP heterogeneous system copy process and tools, for example, Software Provisioning Manager (SWPM). This is not in the scope of this document.

SAP Software Update Manager (SUM) Database Migration Option (DMO)

SAP offers the SUM DMO approach as a one-step migration option from AnyDB to SAP HANA. This option uses the SAP DMO process and tool to automate multiple required migration steps. This is in the scope of this document.

Backup and restore

Backup and restore options are tried-and-true mechanisms for saving data on a source system and restoring it in another destination. AWS has various storage options available to help facilitate data transfer to AWS, including AWS Import/Export Snowball, AWS Storage Gateway, Amazon Simple Storage Service (Amazon S3), and Amazon Elastic Block Store (Amazon EBS). This is not in the scope of this document.

SAP HANA System Replication (HSR)

SAP HANA HSR is a tool for replicating the SAP HANA database to a secondary database or location. The secondary database is an exact copy of the primary database and can be used as the new primary database in the event of a takeover. The advantage of HSR is that it replicates the data directly from source to target. This is not in the scope of this document.

SAP Migration to AWS Cloud: Planning

The planning of SAP migration to AWS cloud consists the following critical elements:

Sizing of SAP ECC on AWS EC2 HANA Instance

First determine the estimated required memory on target HANA instance by running the following steps in the source ECC database, preferably in a copy of production.

Install report /SDF/HDB_SIZING by implementing SAP Note 2462288

Set rdisp/max_wprun_time to 7200

Check and update the database statistics if it is out-of-date

Execute report /SDF/HDB_SIZING

Keep the list of tables field empty

Specify target HANA version

Run in background

A sample output is below

Example of Estimated Required Memory on Target HANA Instance

The result shows a memory requirement totaling 1189 GB. Considering 10% data growth/year for a 5-year plan, the memory requirement would be approximately 2TB. Based on this calculation, the relevant AWS EC2 instance needs to be chosen.

For the network connection between the on-premise data center and AWS, either a VPN or AWS Direct Connect can be used, depending on how much data is required to transfer. The amount of data to transfer correlates to the size of the target SAP HANA database. For example, if the source database size is ~6 TB, the target SAP HANA database size may range from 750 to 1000 GB. This estimate assumes the standard 1:6 or 1:8 times HANA compression ratio, although higher compression ratios can be achieved. So, around 750 GB is required to transfer over the network.

AWS Direct Connect helps to establish a dedicated network connection between customer network and one of the AWS Direct Connect locations. Using industry standard 802.1q VLANs, this dedicated connection can be partitioned into multiple virtual interfaces. This allows using the same connection to access public resources such as objects stored in Amazon S3 using public IP address space, and private resources such as Amazon EC2 instances running within an Amazon Virtual Private Cloud (VPC) using private IP space while maintaining network separation between the public and private environments.

Use DMO with Migration Only Option

DMO is an option of SUM (Software Update Manager) for one-step combined update and migration, including Unicode conversion to SAP HANA in a single downtime window.

The following version of the tool is used here:

SUM 1.0 SP21: The Software Update Manager is available for download on the SAP Support Portal: http://support.sap.com/sltoolset -> System Maintenance.

Software Update Manager (SUM) Scenarios

DMO with SUM 1.0 SP21

DMO without system update:

The DMO offers the option to perform a SUM with DMO run, but without updating the SAP system and hence without the need to provide a stack.xml file. This option is only relevant to carry out a migration of SAP system to the SAP HANA database without updating SAP software. However, the download directory must exist.

To enable a SUM with DMO run for the migration-only scenario, add the following line to the file SAPup_add.par before starting the SUM:

migration_only = 1

The file SAPup_add.par is located in the subdirectory bin of the SUM directory.

SAP Migration to AWS Cloud: Technical Preparation and Prerequisites

Relevant SAP Notes

The following SAP notes need to be checked thoroughly beforehand.

SAP Note Number

Description

2418924

Central Note – SUM 1.0 SP21

2426315

DMO of SUM 1.0 SP21

1912445

ABAP Custom Code Migration to SAP HANA

2205917

SAP HANA DB: Recommended OS settings for SLES 12

1680045

Release note for SWPM 1.0 SP21

1785060

Recommendations for performing migration to SAP HANA

Setup Dedicated Network Between On-premise and AWS Cloud

As described above, a dedicated network (VPN or AWS Direct Connect) needs to be set up in order to eliminate any potential network latency and bandwidth limitations during DMO run.

Configuration

In this roadmap, the following steps are carried out:

The configuration of processes and other performance-relevant parameters: Choose Advanced (Downtime Minimized option) and choose ‘keep archiving off’ during the whole procedure. The number of R3trans and R3load can be chosen based on the Hardware.

Example:

Configuration of Processes and Other Performance-Relevant Parameters

Parameters for Procedure

Provision of connection parameters and users of the target database. For example, SYSTEM, DBACOCKPIT users in HANA database:

Required Migration Specific Passwords

Required DB User DBACOCKPIT Password Input

Checks

In this roadmap, the following steps are carried out:

Calculation of the space for the shadow system

System health checks (such as nametab, transport system)

Checks of relevant tool and system parameters

BI Housekeeping tasks

Preprocessing

In this roadmap, SUM creates the shadow system and the following steps are carried out:

Checks for locked objects

ABAP Workbench locking

Running the shadow system for preparation of new release (ACT_UPG, PARDIST, SGEN)

Transition to the downtime (system isolation). During the preparation of the SAP System for downtime (phases DOWNCONF*), SUM stops and prompts for backup of the complete upgrade directory including all its subdirectories. It is mandatory to carry out a backup of both the source database and the target database

Execution

In this roadmap, the switch to the target system (SAP HANA on AWS) takes place and the following steps are carried out:

Migration of Application data

Repository and Kernel Switch

Adoptions of structures to new release (phase PARCONV)

Main Import (phase TABIM)

XPRAS

Post Processing

In this roadmap, SUM saves the logs files and the following steps are carried out:

Cleanup

SPAU

Transport Unlock

Runtime Evaluation

Procedure Finished Screenshot

SAP Migration to AWS Cloud: Follow-up Activities

Finally, let’s discuss follow-up activities related to SAP migration to AWS cloud. There are several operations that still need to be performed.

Install fresh SAP Application servers on AWS cloud

DMO only migrates the source database to the target HANA database. So, the SAP application servers need to be freshly installed. If the option ‘DMO with System Move’ is selected, this step is not needed. The SAP application server can be co-located with the HANA server (SAP Note 1953429) or can be installed on a separate EC2 instance. The following steps are carried out:

HANA Specific Post Steps

Check HANA DB from DBACOCKPIT. Check for any Missing Tables and indexes from diagnostics

Execute report SHDB_MIGRATION_CHECK to check for any inconsistencies

Diagnostics of DBACOCKPIT

Connect to SAP HANA Studio, check if all the services are up and running. Check the CPU and Memory usage.

SAP Migration to AWS Cloud: Appendix

DMO with System Move

Instead of installing a new PAS, to switch/move the source PAS (Primary Application Server) from On-Premise to AWS cloud target PAS, the DMO with System Move option needs to be selected during SUM phase PREP_INPUT/MIG2NDDB_INI. This option is only supported for non-windows platforms and the target PAS host has to be Linux.

The content of the SUM directory needs to be manually copied to the AWS cloud PAS server during the DMO phase HOSTCHANGE_MOVE. After the transfer, the DMO needs to run again on the target host, provided the SUM archive has been extracted for the target OS type.

Example of serial data transfer mode:

Example of Serial Data Transfer Mode

On AWS, the overview will look like the example below:

Overview of Data Transfer to AWS

Optimize your SAP infrastructure with managed hosting in one of the world’s largest networks of data centers run by Amazon. Ivobe offers services of hosting and SAP migration to AWS cloud. Our hosting enables companies to start new SAP projects without any upfront costs and commitments to investments in expensive infrastructure. New systems can be deployed in minutes and save you not just money, but also time when compared to traditional hosting environments. Visit SAP Hosting page to find out more.